1. Field of the Invention
A wire twisting device and method to join the bare end portions of a plurality of insulated electrical wires to receive a wire connector or wire nut on the outer end portions thereof.
2. Description of the Prior Art
Wire nuts or wire connectors are used in electrical work to connect wires together. These fasteners are generally conically shaped and have either flanges or ribs that a worker can grip as the connector is applied. Unfortunately such wire connectors are small, tend to cause hand cramps and muscle fatigue after repeated installations. Proper connection torque is also difficult to achieve when numerous or heavy gauge wires are connected together.
A number of tools have been developed to apply a wire nut or wire connector directed to the bare ends of elecrical wires.
U.S. Pat. No. 3,769,862 describes a wire nut tool including a sleeve having an open end and an opposite connecting end, a first cavity in the sleeve proximate the open end sized to receive at least a portion of a wire nut and a second opening proximate the opposite end of the sleeve sized to receive a second wire nut. Slots are formed in the sidewalls of the sleeve proximate the open end for receiving the turning wings of a first wire nut and second slots are positioned in the sidewalls of the sleeve proximate the connecting end for receiving the turning wings of a second smaller sized wire nut.
U.S. Pat. No. 2,959,995 shows a wrench comprising a hollow, cylindrical socket member having work-engaging bores of different sizes in opposite ends, with means intermediate the ends of the socket providing a triangular hub portion in rigid concentric relation thereto for thumb and finger manipulation. The sides of the triangle are concave to define nonslip thumb and finger grip areas on the sides of the triangular hub.
U.S. Pat. No. 2,966,083 teaches a wrench for use with wire connectors of the pigtail type comprising a tapered body portion, arms outstanding from the large end of the body portion with amnually operable tabs on the arms and a central tapered fluted cavity open at both ends in the body portion to rotatively and releasably interlock with the exterior of a connector.
U.S. Pat. No. 4,823,650 describes a power driven wrench used to fasten and secure helical spring wire connectors consisting of a cone shaped plastic housing and a hexagonal shaft that extends outwardly from the bottom of the housing. The shaft is placed within a chuck of standard power tools such as power screwdrivers. The housing is open at the top and hollow inside to receive the connectors. Two slots are placed within the walls of the housing to receive and hold the wings or flanges of the connectors. Two slots are placed within the walls of the housing to receive and hold the wings or flanges of the connectors. A number of ribs, concentrically placed around the inner wall of the housing, engage ribs placed on certain types of connectors that have no flanges. The ribs prevent free rotation of the connector within the housing. A magnet embedded within the bottom of the housing holds the connector within the housing.
U.S. Pat. No. 3,902,005 shows a screw-on type wire connector comprising a housing tubular shell member closed at the distal end formed of a deformable insulating plastic material having an axial bore including a proximal inwardly tapered throat section joining an inwardly tapered intermediate section provided with longitudinally extending raised flats arranged in quadrature and joining by a tapered shoulder, a slightly tapered distal bore of reduced cross section. A tapered elongated helical wire coil nests in the housing bore with its narrow inner end force fitted in the distal bore and extending short of the closed end and the wire end of the coil engaging and distorting the flats in the intermediate bore section. Upon application to a pair of wires, the coil self-threads into the flat faces and distal bore faces.
U.S. Pat. No. 4,227,040 teaches a screw-on electrical connector containing a plastic insulating cap with a coil spring on the inside constructed and arranged to be screwed down on the stripped ends of two or more electric wires. The connector is constructed to provide a variable and controlled spring rate or compression load on the stripped ends of the largest number of wire combinations.
Re. 24,074 describes an electrical connector with means for connecting two conductor ends together comprising a hollow cylindrical splice cap, a plurality of electric conductors extending within the splice cap, the splice cap being deformable at spaced points to electrically and mechanically connect the conductors and to provide exterior depressions. A separable resilient insulating member extends over the splice cap and the ends of the conductors and is adapted to be applied over the splice cap after formation of the depressions. The insulating member has a section with a smooth cylindrical outer surface and a retaining member slidable over the section of the insulating member to a position over the depression where the retaining member forces a portion of the insulating member into firm engagement with the depressions to prevent accidental removal of the insulating member from the splice cap.
In addition, various wire twisting tools and machines have been designed to twist or join a plurality of wires.
U.S. Pat. No. 3,168,118 describes a wire twisting device comprising a head or tip with a shaft-like member. The head including means to seize a pair of crossed wires and twisting the wires in a uniform member.
U.S. Pat. No. 2,949,939 shows a wire splicer comprising an elongated U-shaped frame having spaced parallel end walls, a wire-clamping means and a rotary wire support means. The clamping means includes recesses for removably holding wires to be spliced. The rotary means including a shaft to provide a take-up for contraction of the wires and the shaft includes bores for receiving wires held by the clamping means whereby the wires are adapted to be intertwisted upon rotation of the shaft.
U.S. Pat. No. 3,026,915 teaches a wire twister capable of twisting wires of different sizes without the need of adjustment comprising a first rotataable member having a radially directed flange at one end, a pair of jaw members attached to one face of the flange, a pair of cam elements fixed to one face of the second flange and positioned to engage portions of the jaw members to urge them into wire gripping positions when the rotatable members are rotated and spring means to cause the cam elements to urge the jaws into wire-releasing positions.
U.S. Pat. No. 3,990,486 describes a device comprising a solid cylinder which will receive wire within grooves. The cylinder is removably received within a collar or sleeve, after which the extending loop is held and the assembly is rotated a number of times, which produces a twisted length of wire.